I'm also interested: are there problems with opening up this API beyond needing to freeze it and keep it stable? it's pretty stable. As @DeveloperApi at least? Are there implications for storing UDTs in particular engines or formats? Just making it public for developers, even with a 'use at your own risk' warning, seems pretty small as a change?
On Thu, Jan 28, 2021 at 5:10 PM Fitch, Simeon <fi...@astraea.io> wrote: > Hi, > > First time posting here, so apologies if I need to be directing this topic > elsewhere. > > I'm the author of RasterFrames, and a contributor to GeoMesa's Spark SQL > module. Both make use of decently low level Catalyst constructs, include > custom UDTs; RasterFrames introduces a geospatial raster type, and GeoMesa > a geometry type. > > In order to make this work we've circumvented the [`package private`]( > https://bit.ly/3pr0fVv) restriction on `UDTRegistration` by inserting > sibling classes into the package namespace. It's a hack, and works fine > with JVM 8, but violates the [much more restrictive]( > https://bit.ly/3aadO5g) module constructs in JVM 9+. > > We've been monitoring [SPARK-7768]( > https://issues.apache.org/jira/browse/SPARK-7768) (filed in 2015) and > it's [associated PR](https://github.com/apache/spark/pull/16478) for > years now, but it keeps getting kicked down the road(map). > > As authors of open source systems we completely understand how and why > this happens, but we are at a critical juncture in our projects' lifecycle, > anchored to JVM 8 while other systems have moved on to later versions. We'd > also like to enjoy the benefits of later JVMs. > > So... I'm here to find out how I and others critically needing public > access to `UDTRegistration` might better advocate for it? > > I think (but not 100% sure) the PR linked above is more extensive than > what we need, also addressing usability around Encoders, for which we have > our own type class solution. My assumption to date has been all we need is > line 32 of `UDTRegistration` deleted (if there's folly therein, please say > so!). While I understand a reluctance to promote `UDTRegistration` to > `public`, I note that it has not been changed since 2016, perhaps a good > indicator that the API is stable enough. Marking it as `@Experimental` > could be a compromise option. > > Thanks for reading this far and giving this consideration. Any and all > advice is appreciated. > > Simeon (@metasim) > > > -- > Simeon Fitch > Co-founder & VP of R&D > Astraea, Inc. > >
